Re: Can a power supply have too much current?

["Michael J. Mahon" <mjmahon@aol.com>]

Tristan Mumford wrote:
> Michael J. Mahon wrote:
>
>
> > Tristan Mumford wrote:
> >
> >
> > > Still on topic I believe. Is there a way of providing a load to a supply
> > > without connecting it to "real" electronics like a computer? And if so
> > > how many voltages need to be loaded to stabilise it? Just the one?
> > > It's just I have a few supplies, all XT unfortunately, that were stored
> > > for aeons with the dead clone. I want to be able to check them with the
> > > only maximum potential fatality being a few cm of fusewire in the house.
> >
> > I use a 5 Ohm 20W resistor for the +5v and a 10 Ohm 20W resistor for
> > the +12v lines to check out supplies.
> >
> > One is usually enough, but verifying that both positive voltages
> > are in spec at about 1A makes me more comfortable that the supply
> > is actually OK.
>
>
> Those are some big resistors. What you suggest have about the same power
> dissipation as a car indicator globe.

Right.  They are about 1.5cm in diameter and 5cm long, ceramic coated.

Incandescent bulbs have a temperature-dependent resistance, so they're
a little less predictable in their loading of constant-voltage power
supplies.

-michael

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